Description

The SHR-E360 provides heading and sensor information. It includes a high accuracy triaxial fluxgate magnetometer, a triaxial accelerometer, and an angular rate gyro. This unit is a “strapdown” or “body-axis” sensor. The sensitive axes of the SHR will stay at a constant relationship with the vehicle and move as the vehicle moves. Since the fluxgate sensors rotate with the unit, it must use its angle sensors to calculate the rotation back to level. This function is similar to a mechanical gimbal except that the rotations are done using software. The SHR-E360 has several advantages over using a traditional gimbal including: no bearings to wear out, no fluid to leak and high shock survivability.

The SHR-E360 is gyro stabilized. This means that the SHR will provide better performance in dynamic applications. The internal gyro allows the SHR to respond to short-term movements while the fluxgate provides the long-term heading reference. This combination of components allows for accurate data in a wider range of applications than a heading sensor without gyro stabilization. The Watson Industries strapdown gyro solution provides a better magnetic heading than other magnetic heading products using mechanical gimbals. A significant problem with mechanically gimbaled compasses becomes apparent when trying to calibrate the heading sensor in the field. With a strapdown system, the magnetometers are fixed with respect to the vehicle in which it is mounted; Therefore, the constant soft and hard iron field distortions can be fully calibrated out.